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arXiv · 1605.01431

High spatial resolution optical imaging of the multiple T Tauri system LkHα 262/LkHα 263

S. Velasco·R. Rebolo·A. Oscoz·C. Mackay·L. Labadie·A. Pérez Garrido·J. Crass·A. Díaz-Sánchez·B. Femenía·V. González-Escalera·D. L. King·R. L. López·M. Puga·L. F. Rodríguez-Ramos·J. Zuther
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Abstract

We report high spatial resolution i' band imaging of the multiple T Tauri system LkH$α$ 262/LkH$α$ 263 obtained during the first commissioning period of the Adaptive Optics Lucky Imager (AOLI) at the 4.2 m William Herschel Telescope, using its Lucky Imaging mode. AOLI images have provided photometry for each of the two components LkH$α$ 263 A and B (0.41 arcsec separation) and marginal evidence for an unresolved binary or a disc in LkH$α$ 262. The AOLI data combined with previously available and newly obtained optical and infrared imaging show that the three components of LkH$α$ 263 are co-moving, that there is orbital motion in the AB pair, and, remarkably, that LkH$α$ 262-263 is a common proper motion system with less than 1 mas/yr relative motion. We argue that this is a likely five-component gravitationally bounded system. According to BT-settl models the mass of each of the five components is close to 0.4 M$_{\odot}$ and the age is in the range 1-2 Myr. The presence of discs in some of the components offers an interesting opportunity to investigate the formation and evolution of discs in the early stages of multiple very low-mass systems. In particular, we provide tentative evidence that the disc in 263C could be coplanar with the orbit of 263AB.

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S. Velasco, R. Rebolo, A. Oscoz, C. Mackay, L. Labadie, A. Pérez Garrido, J. Crass, A. Díaz-Sánchez, B. Femenía, V. González-Escalera, D. L. King, R. L. López, M. Puga, L. F. Rodríguez-Ramos, J. Zuther. 2016-05-04. High spatial resolution optical imaging of the multiple T Tauri system LkHα 262/LkHα 263. https://doi.org/10.1093/mnras%2Fstw1071

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